Optimal allocation and technoeconomic analysis of solid state transformer in distribution network

The dynamics of power flow in distribution networks have evolved over time, leading to significant voltage deviations and increased power losses. This necessitates a smarter and more versatile replacement option for conventional line-frequency transformers. The solid-state transformer offers a dual reactive power support feature, providing reactive power to both the load and the grid. This capability contributes to power loss reduction and voltage profile improvement, in addition to performing the basic function of voltage transformation similar to line-frequency transformer. However, the high cost and low efficiency of solid state transformers pose challenges to their widespread adoption as replacements for line frequency transformers . The present study focuses on analyzing the financial implications of active power loss reduction achieved by solid transformers, thereby justifying their replacement of line-frequency transformers in distribution networks. Optimal allocation of solid state transformers in the distribution network is conducted considering active power loss and cost as objectives, using mixed-integer nonlinear programming solved in GAMS software. Additionally, a technoeconomic analysis is performed to assess the net savings in yearly operation of a distribution network utilizing solid state transformer than line frequency transformer. The study utilizes real-time load and tariff data and is implemented on the standard distribution networks. • MINLP model proposed for SST planning in distribution networks. • SSTs can replace LFTs to cut costs and improve network performance. • Sensitivity analysis done on SST ratings and loading levels. • Time-of-run analysis shows convergence speed of proposed method. • Analysis includes DGs, power devices and network reconfiguration.